Wednesday's Ask the Experts: VCT discoloration

Wednesday''s Ask the Experts question from a cleaning professional on the International Custodial Advisors Network (ICAN) "Ask the Experts" page: I have VCT to clean and it has a yellow discoloration in the traffic lanes. How can we get the yellowing out and what causes it? How do we stop it?

The answer:

To start, I would recommend a full strip of the finish in those areas showing the discoloration to see if it is in the finish or in the tile itself. If it is in the finish, you will have to locate the source, which may be asphalt seal from the parking lot or walkway. Or, it may be due to new finish sealing in soils ground into the surface in those sections most heavily trafficked. These problems can be averted by using matting and by proper refinishing of only completely clean surfaces. If the tile itself has the yellowing, something has ... — Lynn E. Krafft, ICAN/ATEX editor